Bulgaria accused Lebanese militant movement Hezbollah on Tuesday (NZT Wednesday) of carrying out a bomb attack on a bus in the Black Sea city of Burgas that killed five Israeli tourists last year.

The conclusions of the Bulgarian investigation, citing a clear connection to an attack on European Union soil, might open the way for the EU to join the United States in branding the Iranian-backed Hezbollah a terrorist organisation.

Three people were involved in the attack, two of whom had genuine passports from Australia and Canada, Bulgarian Interior Minister Tsvetan Tsvetanov told reporters after Sofia's national security council discussed the investigation.

"There is data showing the financing and connection between Hezbollah and the two suspects," Tsvetanov said.

"What can be established as a well-grounded assumption is that the two persons whose real identity has been determined belonged to the military wing of Hezbollah."

Israel blamed the attack in Burgas, which killed five Israeli tourists, their Bulgarian driver and the bomber, on Iran and Hezbollah, a powerful Shi'ite Islamist militia that is part of the Lebanese government and waged a brief war with Israel in 2006.

Iran has denied responsibility and accused arch-enemy Israel of plotting and carrying out the bus bombing last July.

Hezbollah, designated by the United States as a terrorist organisation in the 1990s, had no immediate reaction to the announcement.

Israeli Prime Minister Benjamin Netanyahu accused Hezbollah and Iran of waging a "global terror campaign", saying the Burgas bomb was among a series of such attacks carried out in Thailand, Kenya, Turkey, India, Azerbaijan, Cyprus and Georgia.

"The attack in Burgas was an attack on European soil against a member of the European Union. We hope the Europeans will draw the necessary conclusions about the true character of Hezbollah," Netanyahu said in a statement.

EU ASSESSING RESULTS

The Netherlands considers Hezbollah a terrorist group and said in August that the EU should also do so, which would mean Brussels could act to freeze Hezbollah assets in Europe.

Britain reserves the designation for Hezbollah's armed wing, but other EU member states, which have blacklisted the Palestinian Islamist group Hamas, have resisted US and Israeli pressure to do the same to Hezbollah.

The United States urged Europe and others to work on uncovering the Hezbollah's infrastructure and disrupt its financing schemes and networks to prevent future attacks. Hezbollah poses a growing threat to Europe and the rest of the world, a senior US official said.

A spokesman for EU foreign policy chief Catherine Ashton said there was a need to reflect on the outcome of the investigation and the bloc and its member states would discuss an appropriate response based on the investigation.

Bulgaria, a member of Nato as well as the EU, had previously said that the bombing was plotted elsewhere and carried out by foreigners. Even so, that attack stoked tension in a country where Muslims make up some 15 percent of the 7.3 million population.

All three people involved in the attack had fake US driving licenses that were printed in Lebanon, Tsvetanov said.

The two suspects with Canadian and Australian passports had been living in Lebanon, one since 2006 and the other since 2010.

No one has been arrested in connection with the attack and Tsvetanov said he hoped Australia, Canada and Lebanon would cooperate with the continuing investigation.

A senior Israeli official said there had been some doubt in Israel over whether Bulgaria's report might be changed at the last minute because of political pressure, and was hopeful the EU would now blacklist Hezbollah.

"The key is getting France on board. That's where the center of gravity is on this matter," said the official, who spoke on condition of anonymity.

French Foreign Minister Laurent Fabius said in September that an EU blacklisting of Hezbollah was justified only if there was a legal case to pin this on. His remark also appeared to reflect concern that such a move could destabilize Lebanon.